Flap



April 26, 1938, y E F', ZAPARKA 2,115,225

FLAP

' Original Filed Aug. 7, 1933 5 Sheets-Sheet l @www April 26, 193s. E. F. ZAPARKA 2,115,225

FLAP

Original Filed Aug. "7, 1933 5 Sheets-Sheet 2 v /3 27 2f 2324 3mm FLAP original Filed Aug. 7, 195s 5 ,sheets-sheevts @www n April 26, 193s. E. F. ZAP/mm FLAP original Filed Aug. 7, `1935 5 sheets-sheet 4 nl'. l

April 26, i938,

Y E. F. ZAPARKA 2,115,225

FLAP

Original Filed Ag. 7, 1933 5 Sheets-Sheet 5 l SI M93, sp K r Guam/ga Patented Apr. 26, 1938 PATENT OFFICE FLAP Edward Frank Zaparka, Baltimore, Md., assignor to Zap Development Corporation, Baltimore, Md., a corporation of Delaware Application August 7, 1933, Serial No. 684,048 Renewed September 13, 1937 2 Claims.

My invention relates to a flap operating mechanism, and more particularly to an operating mechanism for extending and retracting aps adapted to operate in an air stream through which an aerodynamic device is moved.

Particular embodiments are shown, but it is to be understood that I am not to be limited in the scope of my claims to any particular embodiment. In the drawings my ap is shown mounted near the trailing edge of a wing.

In my copending application Serial No. 657,133 I have explained the advantages of the type of wing ap whose trailing edge moves in a straight line directly below the trailing edge of the wing. Another way of stating this is to say that the movement of the trailing edge of the flap is such as to cause it in extended positions to lie within the locus of perpendiculars drawn to the datum lines of the wing sections and which pass through the trailing edge ofthe wing. Such a flap construction minimizes the shift in center of pressure on the wing upon movement of the ap into operative position, `and at the same time increases the lift of the Wing.

This application shows improvements on the type of ap shown in application 657,133. Such improvements comprisey means for more accu- 'rately controlling the movement of thetrailing edge of the iiap. In the particular embodiments shown the trailing edge of the ap isv designed to move in a straight line and downward directly below the trailing edge of the Wing. The mechanism is so adjusted as to give a more accurate control in this movement of the trailing edge than has heretofore been possible with the mechanisms previously employed A The inherent advantages of this close line approximation of the movement of the flap within the zone of theoretically greatest efliciency, produce desirable characteristics which are an improvement upon the aps previously disclosed.

My mechanism can be so adjusted as to give the desired movement of the flap Within quite small limits of tolerance; limits considerably smaller than heretofore possible with other mechanisms. p

My aps can be used in places other than on wings, such as on control surfaces, or in other positions on either heavier or lighter than air craft of dierent types. .m

Fig. 1 is a side elevation of an airplane showing my ap in operative position on a wing, `the control mechanism being indicated somewhat schematically by dotted lines. l

Fig. 2 is a detailed view of the operating-mechanism for controlling the position of the wing flaps, the parts being broken away to save space.

Fig. 3 is a vertical section taken through the trailing edge of a wing, showing the flap pivoting mechanism, the extended position of the ap 5 being shown in the dotted lines.

Fig. 4 is a top plan detailed view of the operating mechanism for moving the flaps into and out of their nested position at the rear of the wing.

Fig. 5 is a graph showing the geometric posi- 10 tions of the parts when extending the ap shown in Figs. l to 4 inclusive.

Fig. 6 is a vertical section taken through a wing showing another type of flap and operating mechanism. 15

Fig. '7` is a View taken along the lines l-'l of Fig. 6 looking in the direction of the arrows.

Fig. 8 is a perspective View showing the housing for the link support for the iiap.

Fig. 9 is a graph depicting the geometry of operation of the ap shown in Figs. 6 to 8 inelusive.

Referring to the drawings I have shown an airplane having a fuselage l, a motor 2 and a propeller 3. The empennage surfaces I have indicated generaily by the numeral 4, which comprise the usual stabilizer, elevator and rudder surfaces. The plane is of the monoplane type and is provided with wings 5, each of which is provided with a wing flap 6. Mounted over each of the Wings are ailerons l on supports 3. The ailerons are provided with aileron horns 9 to which operating rods l0 are attached. The mechanism for operating the ailerons l mounted over therear of the wings has been covered in other Icopending applications, and it is not thought necessary to describe their functions and construction in detail.

The iiaps 6 are of the type which are so mounted that their trailing edges shalllie within the locus of perpendiculars drawn to the datum line of the wing sections and which pass through the trailing edges of the wings.

The aps 6 are adapted to have their trailing edges travel in substantially va straight line in being extended or retracted. Heretofore, for instance in my a'pplication Serial No.` 657,133, I haveindicated'that this movement of the trailing edge of the flaps was desirable. 'Ihe mecha- 50 nism which I here show, however, 4gives a more Vaccurate control over such movement, and the positions of the ap during its movements under the control of the operating mechanism moreA closely approximate the theoretically perfect ,f

than is possible with any of the constructions shown in my other copending applications.

The flaps 5 are provided with a lower iiap member II which may be of sheet metal over which ts a member I2 having corrugations which run in the opposite direction from thecorrugations I3 on the member II. 'I'his construction gives great strength and rigidity with little weight.

Attached to the upper surface I2 of the flap 8 are angular support pieces I4 which may be riveted or otherwise suitably attached to the upper surface. These angular support pieces are provided with upstanding sides I5 which are at one end extended into an upstanding member I5 which carries a rod I1 having thereon pivot pieces or rollers I8 carried at its ends. The pivot pieces or rollers I8 are adapted to t within stop or .guideways I9 formed in supports 20. Ihe supports 20 are of angular configuration, there being a pair of supports 20 at each station where a ap operating mechanism is located. There are generally a series of stations along each wing. In Figure 4 I have shown two stations, though there may be more, or in some instances one station may sumce.

The supports 20 are flanged at their outer edges for greater strength and rigidity, and also anged in proximity to the slots I9. The supportsl 20 are fastened by bolts 2I to a rear wing on its pivot 21 without binding the ap in its l movement. Y 1

The length of the link 25 and the convolution of the slot I9 is such that upon movement of the rollers I8 rearwardly the flap is opened, as indicated in dotted lines in Fig. 3, to cause the rear or trailing edge of the iiap to fall, in all of its extended positions. within very close ranges of tolerance 'within the locus of perpendiculars to the datum lines of the wing sections. which pass through the trailing edges of the wing.

It Will be noted that the slot I9 is not shown as proceeding in a straight line, but is provided l i with convolutions as shown in Fig. 3, and the convolutions are such as to accurately determine that the trailing edge of the ap shalllie within the defined locus which may be indicated as the opl through U-shaped ends'3I of rods 32. The rodsl 32 are pivoted at 33 to one end of an arm 34 of a bell crank lever 35 which is pivoted at 35 on a triangular support construction 31.

'Ihe triangular support construction 31 isrprovided with cut-out portions 38 to lighten the con- 'bell crank 35 to operate the iiaps.

struction. Thesupports 31 are offbox-iike con-` struction and provided with apertures, as indi- 44 which is screw-threaded to a shaft 45. There are twoshafts 45, one for each wing.

The operating head 44 also carries one end of an operating link 45 `which is adapted to operate another bell crank 35 at a remotestation. The number of bell cranks and the number of linkages to operate them can be multiplied beyond two, as above set forth.

Each shaft- 45 is connected through a gimbal joint 41 to another shaft 48, on which is mounted a beveled pinion 49. The beveled pinion 49 meshes withv a beveled pinion 5I mounted onl a shaft 52. Theshaft52, at its other end, carries a beveled pinion 53 which meshes withY a beveled pinion 54 mounted on a shaft 55. A hand crank 56 is adapted to rotate the shaft 55, and through the shafts and pinions indicated the shaft 48 may be rotated in either direction of rotation desired by the pilot.

The rotation of the shaft 48 through the gimbal joint 41 rotates the shaft 45 to operate the flaps. The rotation of the shaft '45 moves the operating head 44 in `either direction, depending upon the direction of rotation -of the shaft 45 and this, through the bell crank linkages, pulls or pushes on rods 32 to raise or lower the iiaps.

Similar or equivalent mechanism can be used to operate flaps for control surfacesor even to operate aileron flaps, or flaps in any position where they may be employed in either lighter or heavier than air craft.

'Ihe geometry of the moving parts is graphically illustrated in Fig. 5, where the movement of the pivot pieces along the tracks I9 is indicated. The movement of the pivots 21 is indicated at the point marked"Link movement.

Y The movement of the trailing edge of the iiap is shown.

I have indicated in Figs. 6, 7 and 8 another form 'of flap operating mechanism in which the trailing edge of the flap very closely approximates the theoretically desirable movement above set forth. 'In this case the shaft 45 is provided with a series of beveled pinions 51 which engage with beveled pinions 58 carried on operating rods 59 thatvare journaled in journals 6I which are carried by the rear wing spar 22. There is an operating rod located at each flap operating station in each wing. The construction at the `rear of the wing comprises bracing members 53 which are attached, through the bolts 2|, to the rear wing spar 22. 'I'he operating rod 59 is journaled at 64 at the rear of the bracing members 53.

The operating rods 59 are provided with screwthreaded sections on which ilt operating heads vI5 which may be keyed, as indicated at 51, to keyways 58 carried by the support members 53. The

construction of the flaps 6 is almost identical withV- that previously disclosed. The upstandng members I5 are pivoted-at 59 to the operating heads 55. Pivoted at the pivot points 21 on the flaps 5 are'links 1I, which may have bent portions 12 to permit free movement ofthe flap and the links. 'Ihe links are further bent, as indicated at`.13',

, and are pivoted at 14 to supports 15 which-may be extensions of the support members 63.

Stream-lined housings 16 are formed at each: station, as indicated in the drawings, to streamline the support for the .links 1I. It will be noted that by the use of such stream-lined housing, the links A1I may be pivoted substantially in line with the traiiing'edge of the wings ,5. The pitch V.of .the screw-threaded portions 55, the length of the links 1I and the length of the flap, and other factors, are such as to insure that the trailing edge of the flaps shall lie within very close approximation to the theoretically desirable position, in which the trailing edges of the aps lie directly below ythe trailing edges of the wings, and, substantially in the locus of perpendiculars to the wing chords which pass through the trailing'edges of the wings.

In Fig. 9 the geometry of moVemeL-tof the parts of the type of flap depicted in Figs. 6, 7 and 8 is shown. It will be seen that the trailing edge of the ilap can be held within a Very close approximation to the theoretically desired movement.

I claim:

1. A wing ilap mechanism comprising a wing, a rear spar for the wing, a iiap pivotally supported below the wing, ilap operating mechanism comprising a member mounted on the rear spar oi the Wing and extending rearwardly therefrom Within the wing and formed with a cam slot, a support attached to the iiap, a pivot piece supported by said support, a link pivoted below the upper surface of the wing at one end and to the ilap at the other end, said pivot piece on the upstanding member being adapted to lie Within said cam slot whereby the trailing edge of the flap shall move within small limits of tolerance within the locus of lines drawn perpendicular to Y the datum lines of the Wing sections and which pass through the trailing edge of the wing.

2. A flap mechanism comprising a Wing, a ap pivotally supfmrted below the Wing, ap operating mechanism all Without the airstream and comprising a, support secured to the wing structure and extending in a fore and aft direction 1 Within the wing and having a guiding cam ,slot formed therein, a link pivoted at one end to said support and at the other end to said flap at a point spaced rearwardly from the nose of the ap,

a pivot piece secured-to the ap adjacent the 1 nose thereof and cooperating with said guiding cam slot, the convolutions of said' cam slot being such as to insure that the trailing edge of the ap shall move Within small limits of tolerance within the ylocus oi lines drawn perpendicular to 2 the datum lines of the Wing sections and which pass through the trailing edge of the wing.

EDWARD FRANK ZAPARKA. 

